Turba is the Horde contact management application. It is a production level address book, and makes heavy use of the Horde framework to provide integration with IMP and other Horde applications. It supports SQL, LDAP, Kolab, and IMSP address books.

Ingo is an email-filter management application. It
is fully internationalized, integrated with Horde
and the IMP Webmail client, and supports both
server-side (Sieve, procmail, maildrop) and client-side
(IMAP) rule creation.

Java Serialization to XML (JSX) serializes/deserializes Java objects to/from XML, so you can save them, send them - and see them! It correctly handles the many Serializable classes in Java and third-party libraries that use Java's builtin Java Object Serialization (JOS) to customize their serialization (for security, validation, faithful deserialisation, and class evolution).

Clam AntiVirus is an anti-virus toolkit designed especially for email
scanning on mail gateways. It provides a number of utilities, including
a flexible and scalable multi-threaded daemon, a commandline scanner,
and a tool for automatic database updates. The core of the package is an
anti-virus engine available as a shared library.

MLAPD manages mailing lists posting accesses. Its goal is to read the data from LDAP. It works as an access policy delegation agent for Postfix, listens on a TCP socket, and can be queried concurrently by multiple Postfix instances.

astGUIclient is part of a suite of programs that are designed to
interact with the Asterisk PBX Phone system at a client computer level
to extend the functionality of your phone and system. The main GUI
application, astGUIclient, is a set of PHP Web-based scripts utilizing
Javascript and XMLHTTPRequest functions that work through a browser to
give realtime information and functionality with nothing more than an
Internet browser on the client computer. Another component included with
the astGUIclient package is the VICIDIAL auto-dialer, a list dialer
which can dial one-call-at-a-time or be put in auto-dial mode to act as
a predictive dialer. It can function as an ACD for inbound calls or for
Closer calls coming from VICIDIAL fronters, and allows for remote agents
that may only have a phone.

GroupOffice is a groupware suite that takes your office online, implementing online collaboration and CRM. It allows you to share projects, calendars, files and email online with co-workers and clients. It is easy to use and fully customizable. It also features synchronization with PDAs and Outlook.